A variety of systems for sampling various materials are known. However, numerous disadvantages and shortcomings exist with prior systems, and there is a need for improvement to overcome such disadvantages and shortcomings. Some examples of sampling devices of the prior art are disclosed in U.S. Pat. Nos. 4,433,587 and 4,082,004.
The sampling systems of the prior art have several drawbacks. Some such drawbacks are that the sampling systems of the prior art have numerous functioning parts which can lead to the use of higher-cost components and to longer assembly times. It would be preferable to have a sampling device which has fewer components such as a body which functions as both the process tube and air cylinder. It would also be preferable to have a sampling device which includes an offset tube as well as an air cylinder piston which prevents rotation of the tube and maintains the aperture in proper alignment with process flow. It would also be preferable to have a sampling device that requires few or no tools to assemble or disassemble as well as clean and maintain.
In processes that convey bulk solid and friable powder media in a process pipeline (or process tube), there is a need to extract a sample of the process medium without affecting the material properties. Current samplers employ a tube that extends into the process pipeline (or process tube) and an aperture on the side of the tube which then allows process media to enter the sampler. The process media then are allowed to travel through the tube and be collected in a receptacle. The tube is then retracted from the process pipeline. Proper extraction of the sample requires the aperture of the sampling tube to be facing in the direction of flow of the process medium. Currently, there are a number of methods to ensure rotational alignment which generally include the use of fixtures, effectors and apertures on pneumatic cylinders attached to sample extraction devices. These include using anti-rotation pins, dual piston rods, linkages and dual support bars. All of these methods involve the added complexity of extra parts, seals and wear points. It is to these needs that this inventive sampling apparatus or device is drawn.
The present device uses a sample conveyance tube with an aperture that allows the process media to enter the tube. The device ensures the aperture maintains proper orientation to the medium flow. The invention allows for extraction of a sample while maintaining aperture orientation to the flow. The inventive apparatus also reduces the number of parts, and therefore the complexity, making it easier to clean and maintain.
The present device maintains simplicity by lowering the part count while providing the critical anti-rotation feature. This is a novel improvement because it maintains the basic shape and form of the air cylinder while still preventing rotation through the offset piston and rod axes and allowing the piston rod in the cylinder to function as the sample conveyance tube. This is a substantial improvement over the samplers of the prior art.
It is to all the above-noted needs that the device of this application is drawn. This invention addresses and overcomes such problems.